As an apparatus that analyzes a component included in a sample such as blood, an automatic analysis apparatus that measures the amount of scattered light or transmitted light having a single or multiple wavelengths generated when light is emitted from a light source to a reaction solution, which is an analysis target, as a mixture of a sample and a reagent is known.
Examples of the automatic analysis apparatus include an apparatus for biochemical analysis that performs qualitative and quantitative analysis of a target component in a biological sample and an apparatus for blood coagulation analysis that measures coagulability of blood as a sample in the field of a biological examination or a hematological examination.
Here, in a case where a decrease in light amount caused by deterioration of the light source or incorporation of foreign matter into an optical path occurs, the reliability of analysis deteriorates such that a false result may be reported or the analysis may fail. Therefore, a biochemical automatic analysis apparatus including a reaction container that is cleaned to be repeatedly used has a function of cleaning the reaction container before a start of analysis, performing photometry (blank measurement) of transmitted light or scattered light in a state where only water is put into the cleaned reaction container, comparing the measurement result and a reference value to each other to detect scratches or contamination of the reaction container or incorporation of foreign matter into an optical path, and notifying an operator not to use the reaction container in a case where the reaction container is abnormal.
On the other hand, in an automatic analysis apparatus that performs analysis such as blood coagulation analysis of measuring scattered light using a disposable reaction container, light is not incident on a detector in a state where a reaction container and a reaction solution are not present. Therefore, blank measurement cannot be performed per analysis operation. Accordingly, in order to check a deterioration state of a light source or incorporation of foreign matter on an optical path, regularly or in a case where an abnormal analysis result occurs, the amount of light incident on the detector is measured by providing a standard material called a standard solution or a standard scatterer.
In an automatic analysis apparatus described in PTL 1 in which a light source is arranged below a disposable reaction container to measure scattered light, a light detector is provided in a transport mechanism of the reaction container to measure the amount of light emitted from the light source. In this configuration, deterioration of the light source or foreign matter in an analysis port can be detected by measuring the light amount under either condition irrespective of whether or not the reaction container is held by the transport mechanism.